The present invention relates to display of still or moving images and, in particular, it concerns systems and methods for enhancing perception of the content of displayed images.
All imaging hardware systems are inherently limited in the level of detail and the fidelity of images they produce. Such limitations include spatial resolution, dynamic pixel range, optical distortions, background noise levels and overall sensitivity. Particularly when pushed to their performance limits in cases of high magnification, poor illumination, motion or other environmental disruptions, image quality may be seriously impaired. Examples of image impairment include, but are not limited to, loss of contrast and blurring. Image degradation may also be caused by subsequent handling of image data such as by data compression and changes of format. For these and other reasons, situations occur in which the details of various still or moving (video) images are not readily perceived by the human eyes.
There exist many image processing techniques which can be useful for emphasizing specific information in a poor quality image. Examples of such processing techniques include, but are not limited to, image sharpening, contrast enhancement and edge detection. Although such techniques are useful for highlighting certain features, they also introduce further distortions into the image. These added distortions may be misleading to the eye and typically cause significant corruption of the overall visual impression perceived by the viewer.
Even where image quality is good, limitations of equipment used for displaying the images sometimes limits the amount of information which can be presented to the eye. For example, certain displays are limited to 8-bit (256 shade) intensity levels, and are therefore unable to reproduce the information in an image stored with a greater dynamic range (such as 16-bit with 65536 shades of intensity).
There is therefore a need for improved systems and methods for enhancing perception of the content of displayed images.